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arXiv · 2502.19157

Proper effective temperature and order parameters in relativistic non-equilibrium steady states

Shin Nakamura·Fuminori Okabayashi
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Abstract

We examine the concept of temperature in non-equilibrium steady states. Using the D3-D5 model of gauge/gravity duality, we investigate spontaneous symmetry breaking in a relativistic (2+1)-dimensional defect moving at constant velocity within a (3+1)-dimensional heat bath. We find that the dependence of the order parameter on both the heat bath temperature and the defect velocity can be captured by a single variable -- the proper effective temperature -- for the moving defect. Our results suggest that the proper effective temperature is an essential parameter for a class of relativistic non-equilibrium steady states.

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Shin Nakamura, Fuminori Okabayashi. 2025-02-26. Proper effective temperature and order parameters in relativistic non-equilibrium steady states. https://doi.org/10.1007/jhep08(2025)069

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